How to project (bake) an environment texture onto a mesh as if from a slide projector?
One cheap and fast way of doing it is to use The unwrap option &quot;Project from view&quot; Like in this Picture:

This uses your current 3D viewport as to unwrap it 1to1 into the UV image editor. If you align your camera just right it behaves like a Projected Image. I recommend to do this in the orthographic 3D view as well.